Sterilizing Your Soil Tutorial

[Monad]

Hi all, I recently needed to sterilize soil I had bought so I figured I'd post a tutorial about it.

Fungus gnats, spider mites, white flies, thrips, mold, weeds, and any other soil problems can be fixed by sterilizing your soil.
Soil bought at large retailers often contains fungus gnats and molds.

Here is How:
All you need to do is cook your soil in the oven to reach an internal temperature of 160-180F.

To kill all pests and molds sterilize your soil to reach a temperature of 160F

To kill weeds and seeds sterilize to 180F

*** Never exceed 212F because this will kill everything including good organisms and leave your soil dry, and susceptible to pests & disease.***​

You will need:

- A pan to place soil in - roasting pans for turkeys and larges meals work great.

- A meat Thermometer

- Tinfoil

Preheat your oven anywhere inbetween 160-180F.
Place the soil in your pan no more than 4" thick.
Cover loosely with tinfoil

Cook in the oven on the bottom rack ( or top if your heating element is on the top )

Cook for 20-45 minutes checking the internal temperature at 20 minutes.

Check your temperature with a meat thermometer in the center of the pan. the sides will heat up quicker so it is important all your measurements come from the center of the pan. You can also give the soil a stir at this point if you'd like.

Continue to heat checking every 5-10 minutes until the desired internal temperature is reached.
Remember: Do not exceed 190F nothing good can come of this

Once your soil is 160F in the center your done!
Cool and store in sterile bags - I put my bags in the fridge for an hour to make sure the soil is cooled.
Now go have a smoke, you deserve it

 

[hela w opalach]

Thanks for the tutorial Monad. I will sterilize my soilmixes.. I always have shitty spiders etc in my box :S

 

[Monad]

Forgot to add - its really important you supplement your soil after doing this since all the nutritional value will be gone.

 

[herbal essences]

what do you think about doing this with coco? recently got a bag with white flies in it

 

[darthvapor]

why not just water the soil with hydroguard or hydrogen peroxide?

 

[Purkle]

now how do you do this on a larger scale?

 

[DocLeaf]

Neat thread ,,,great example of how to sterilize soils on a small scale at home we need more threads like this

Forgot to add - its really important you supplement your soil after doing this since all the nutritional value will be gone.

While the level of micro-organisms will initially be depleted by soil sterilization, sterilization actually presents a level playing field whereby friendly / beneficial micro-organism colonise the fresh soil first, prior to any invasion by unhealthy organisms and soil pathogens later.

Likewise the overall temperatures would need to be far higher to destroy all the organic matter within the soil substrate.

Hope this helps
All the best

 

[wygram]

what you are actually doing here is not sterilization, but pasteurization. mushroom forums have a lot of info about this. especially pasteurization of peat which is done by getting the center of the substrate, as monad said, to 160 for 1 hour. this kills of mold spores and bugs leaving microbial life alive to thrive

 

[Monad]

why not just water the soil with hydroguard or hydrogen peroxide?

Never thought about peroxide...probably cuz I'm cheap.
Looked into it and it would work 1-2 tbsp of 3% per gallon, it'll kill mold too aparently. This would be a great way to clean large amounts of soil.

wonder what it would do to the pH etc?

I'll try the peroxide soon, and post here.
I need to get more soil tommorow, and it'll need to be sterilized.
I'll measure the pH after as well.

Anyone else done this before?

 

[darthvapor]

you could always get serenade in powder form which has bacillus subtillis, same as hydroguard and mix with the soil along with neem oil and some beneficial bacteria and fungus. add some worm castings and mollasses and let it sit for a few weeks. The good bacteria and fungus will take over the bad.

 

[Monad]

I tried the hydrogen peroxide 2.5 tbsp to the gallon an so far so good, soo easy - I'll definately be doing this from now on.
Got a bunch of old soil from ex plants that needs to be revived.
Might give the bacteria a try, and probably some worms.

 

[Fuadfahmie]

Can I just watering the soil with 180 f of hot water ? It is give the same result as cook it ?

 

[emeraldcityog]

I'm gonna guess that hot water would do the same thing as cooking if you could maintain the temp for long enough. Not sure but it's probably close enough. I'd just use H202 or Physan 20 and then reinoculate.